Damper for furnaces.



W. E. FROST.

D'AMPER FOR FURNACES.

APPLICATION FILED Fz.1o.191s.

l ,@@QRUU Patented out. 24, 1916.

' 3 SHEETS-SHEET I. Emil "WIL 1HE NoRms PE1-ens ca., wAsuINGTaN, v. c.

W. E. FROST.

DAMPER FOR FURNACES.

APPLICATIQN FILED FEB. xo. 191e.

l l ,QUQUW Patented oef. 24, 1916.

3 SHEETS-SHEET 2.

W. E. FROST.

DAMPER FOR FURNACES.

APPLICATION FILED FEB. l0. l9l6.

mfmw. Patented, out. 24,1916.

3 SHEETSSHEET 3.

l'fllhllVFlElll FFFCF.

WALTER EDWIN FROST, OF AUBURN, FLAINE, ASSIGNOR OF ONE-HALF T0 I-IOLlVIAN GOULD, OF AUBURN, MAINE, AND ONE-FOURTH 'IO JOHN B. SMITH; OF LEWIS- TON', MAINE.

DAIVIFER FOR FURNACES.

Application filed February l0, 1916.

To all whom t may concern Be it known that I, WALTER E. FRosr, a citizen of the United Sta-tes, residing at Auburn, in the county of Androscoggin and State of Maine; have invented certain new and useful Improvements in Dampers for Furnaces; and I do declare the following to be a full, clear, and exact description of the invention; such as will enable others `skilled in the art to which it appertains to make and use the same.

This invention has reference to certain improvements in furnace dampers of the type intended for use in the fines leading from the furnace to the chimney.

More particularly, the invention has reference to certain improvements in dampers of the foregoing type, and which are intended to permit the entrance of fresh air into the flue, 4which fresh air flows by a counter-current movement back through the lflue into the furnace. Admission of the fresh air into the furnace in this manner serves to supply the necessary oxygen for carrying on the combustion within the furnace at the ordinary or normal rate or intensity, without the necessity of leaving the furnace or ash pit doors open during .the normal operation.

The main object of the invention is to provide a damper of peculiar construction such that incoming air is caused to pass through the body of the damper to be thereby heated by the waste heat which is going up the flue. In this manner; a considerable portion of the waste heat is conserved so that the efficiency or economy of the furnace is greatly improved.` At the same time the pre-heating of the air permits the attainment of a higher temperature of combustion than would otherwise be possible.

Another object of the invention is to so construct the damper that it can be readily inserted into the flue without the necessity of specially constructing the flue; and with-A out the necessity of cutting or opening the Hue other than the forming of a pair of oppositely disposed holes in the flue.

A still further object of the invention is to provide a device of this character in which the flow of air is regulated by a valve.

Other objects and uses will appear from a detailed description of the invention which Specification of Letters Patent.

Patented Oct. 2dr, fgll.

serial No. 77,491. l

consists in the features of construction and combinations of parts hereinafter described and (claimed. 1

In the accompanying drawings in which similar reference characters designate like parts throughout the several views, Figure l is a side elevation of a damper constructed in accordance with this invention, showing it applied to a smoke pipe, the same being shown in section; Fig. 2 is a horizontal sectional view taken on the plane of the line 2-2 of Fig. l; Fig. 3 is a similar View showing the cover plate removed; Fig. 4; is a vertical sectional view taken on the plane of the line L /l of Figs. 2 and 3; Fig. 5 is a similar view taken on the plane of the line 5-.5 of Figs. 2 and 8; Fig. 6 is a modified form of the invention showing the same applied to the smoke pipe, the same being shown in section; and Fig. 'f' is a horizontal section taken on the plane of the line 7 -7 of Fig. 6.

Referring more particularly to the drawings7 the numeral l designates the iue or smoke pipe leadingv from a furnace or boiler to the chimney, and arranged within this pipe l is'a damper 2 to which the present invention relates. As` previously stated, it has been found by experience that fresh airmay be admitted into the flue at a point close up to the furnace, and such air will drop back into the furnace to supply the necessary oxygen for combustion without the necessity of opening the furnace or ash pit doors.

The form of damper shown in Figs. l to 5 of the drawings comprises a casting 3 composed of a metal plate 4 having an annular flange 5 extending laterally from the peripheral edge thereof, and a centrally arranged opening 6, from the edges of which extends a second annular iange 7. Disposed in a tortuous path between the two flanges 5 and 7; is a partition 8, thereby forming an irregular or tortuous channel S for the passage of air therethrough. Fixed in any suitable manner, here shown by bolts 9, to the open side of the casting 3 and tightlyv contacting with the edges of the flanges 5 and 7 and the partition 8, is a circular cover plate 10 which is provided with a central opening 11. Threaded or otherwise secured in a suitable opening in the cover plate 10 adjacent the central opening 11 thereof and in communication/with thechannel vorg-passage 8, is a tubular air outlet pipe or nipple 12. i

The numeral-13 represents a threaded opening arranged in theflange 5 `adjacent the outer or inlet end of the air passage 8,.and threaded in this openingl is: atubular nipple 14 having its outer end shaped V to form a suitable valve seat, for ay purpose to be described. Arranged similarly on the diametrically opposite side of:y the casting?)- is a closed nipple or stud 15. These two nipples 14 and 15l act in the capacity oftrunnions for pivoting -the damperV in suitable openings 16 arranged in the opposite walls of the. smoke pipel. Surrounding the nipple or stud 15 and disposed between the outer side of the pipe lfandfthek inner the 'latter' being integrally connected at lby a.V suitable cap `29.

their.A outer ends by a strap orcross bar 22. This cross b'ar 22 is. provided with a threaded'aperture 23 arranged in alinement with the open outer end ofthe nipple 14, and operatingin thev aperture 23,y is a screw 24, the inner. end of which is cone-shaped and adapted to be disposed inthe valve seat inthe outer openend ofthel nipple 14, for regulating the admission` of andfflow of .air through lsaid nipple and-.the passage through said damper. This handle isL arrangedfin the same general planewith theV damper so that the general position and amount'of opening or inclination of the latter'may be determined by the relative angle .of the handle to the pipe 1, as will be readily understood withoutl further description.

1n Figs. 6 and Tof the drawings, the damperv 2 is composed'ofk a plurality of closely arranged parallel `pipes 25,the ends of the adjacentfonesbeing connected by U couplings 26 asshown, thereby forming a continuous. flat coil through which air may pass. Threadedto. suitable Tcouplings 27 arranged substantially. midway between the ends of the pipes. at, the opposite edges of thecoil, arethe aforesaid trunnions14 and 15, by which the -coil is pivotally mounted in the: pipe 1. ExtendinginwardlyA from the fopen end ofthe pi-pe25 .to which the trunnion 15 is connected, is any air outlet pipe-28, whilethe-free end ofthe pipe 25to whichv the trunniona14 is fastened, is .closed As. shown, the U couplingsiQGy arey .arranged 5in. staggered-.re-

lation in order toA allow the pipes 25 to be 'arranged closely together.

By this arrangement of parts, fresh air from the outside will pass through the nipple 14, the amount, however, being regupassage or channel 8 in the form of damper shown in Figs. 1 to 5 of the drawings to the interior of the pipe 1. During this tortuous passage it will be heated by the hot smoke and gas passing through the pipe 1 around the damper 2 and the central opening-(3,v thus more effectively combining with the combustible gases, as will be readily understood. In Figs. 6 and 7 it will pass through the coil.

From ,the foregoing description, taken in connection with the accompanying drawings, the operation of the invention will be understood without a more extended explanation.

vWhile 1 have herein shown and described only two forms of construction embodying features of` my-invention, still it will be understoodlthat Ifam in nowise restricted to these forms, exceptfas. may be called for in-the claims, but'that 1 include Within the scope of my invention other equivalent arrangements operating in equivalent manners to produce equivalent results.

Iclaim:

1. A device of the class described comprising a damper having an air passage therethrough, trun-nions extending outwardly from the opposite edges of said damper, one of said trunnions having an air passagetherethrough communicating with the passage through' said-damper, a pair of spacedy arms secured to the outer end ofthe last mentioned trunnion and extending substantially longitudinally of the same, a cross bar connecting the outer ends of said arms andv having a threaded aperture therein, and a screw operating in Said aperture and havingits inner end 'disposed in the open end offthey last-mentioned trunnion for regulating theiiow of air throughsaid passages.

2i.- A damper ofthe class described comprising-a fiat'closely formed continuous coil of pipes, trunnions extending outwardly fromutheiopposite edgesof said coil, one of said trunnionshaving an air passage therethrough in communication with a portion of said coil, apair ofspaced arms secured to the outer-end ofthe last mentioned trunnion and eXtendingsubstantially longitudinally ofthe same, across bar connecting the outer. ends of said arms and havinga threaded aperture therein disposed in alinement witlrtheouter endl of said passage, and a screwoperating in said aperture, the inner` end of said screw beingv provided with a conical valve for regulating the iow of air through saidv passage and said coil.

3. A damper of the class described comprising a plurality of closely arranged parallel pipes7 U couplings connecting the ends of adjacent pipes to form a at continuous coil, trunnions extending outwardly from the opposite edges of said coil, one of said trunnions having an air passage therethrough in communication with a portion of said coil, a pair of spaced arms secured to the outer end of the last mentioned trunnion and extending substantially longitudinally of the same, a cross bar connecting the outer ends of saidarms and having a threaded aperture therein disposed in alinement with the outer end of said passage, and a screw operating in said aperture, the inner end of said screw being provided with a conical valve for regulating the flow of air through said passage and said coil.

4. A damper of the class described comprising a plurality of closely arranged parallel pipes, U couplings connecting the ends of adjacent pipes to form a continuous flat coil, a trunnion extending outwardly Jfrom the pipe at one 0I' the edges of said coil, a tubular nipplesecured to the pipe on the opposite edge of said coil and communicating with the interior thereof, a pair of spaced arms secured to the outer end of said nipple and extending substantially longitudinally of the same, a cross bar connecting the outer ends of said arms and having a threaded aperture therein disposed in alinement with the open end of said nipple, and a screw operating in said aperture and having a cone-shaped inner end disposed in the open end of said nipple, whereby to form a valve for regulating the ilow of air through said nipple and said coil.

5. A device of the class described comprising a damper having trunnions extending outwardly from its opposite edges, one of said trunnions being provided with a valve seat at its outer end, a triangularshaped handle having a hub portion iixed to the outer end of the last mentioned trunnion, and a screw adjustably mounted on the cross bar of said handle and having its inner end disposed in said seat.

6. A damper of the class described comprising a plurality of closely arranged parallel pipes, U-couplings connecting the ends of adjacent pipes to form a continuous Hat coil, T-couplings arranged in the outermost plates, trunnions secured to said T-couplings, one of said trunnions communicating with the interior of said coil and having a valve seat therein, and a valve disposed in said seat.

In testimony whereof I have hereunto set my hand in presence of two subscribing wit`- nesses.

`WALTER ED`WIN FROST. Witnesses:

GEO. C. WEBBER, ELIZABETH M. HERBST.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patente. Washington. D. C. 

